FLOW DETECTION IN LIQUID APPLICATION SYSTEMS

摘要

Method and apparatus for detecting normal and abnormal flow conditions in a liquid flow device such as a spray nozzle are provided. Flow conditions are detected by using a sensor disposed external the flow device. The sensor, such as a piezoelectric accelerometer, detects mechanical radiant energy produced by liquid flow. Various circuits are optionally provided to carry out various functions such as detecting normal and abnormal flow conditions, issuing alarm and warning signals, detecting gun on delay, gun off delay, gun on duration, valve events such as open and close, and so on. A last valid averaged sample technique is provided to improve accuracy, as well as a de-bounce feature. Various noise filtering techniques are also described.